It had been feared that the missing workers died as a result of the explosions at the Blue Rhino propane tank factory in Tavares City, Florida.
But all have been accounted for after as many as 15 were initially feared killed, authorities say.
Seven people were injured and transported to local hospitals.
200 firefighters are tackling the blaze and believe they have it under control.
The massive blast from the factory was heard from 10 MILES away.
Aerial footage of the scene shows fires still burning over a large area, shooting large flames and plumes of smoke into the night sky.
A series of explosions can also be heard in amateur videos filmed by nearby residents.
Lake County Sheriff Gary Borders says the blasts occurred inside the plant and blew the roof off the bulding.
Lisa Garner told local paper the Orlando Sentinel: "I heard a loud bomb sound.
“We could see the flames and the initial explosion knocked us off our feet”Local businessman Jim Mueller
"I thought somebody had run into my house."
Local businessman Jim Mueller told Sky News: "They're evacuating everything within a mile.
"We could see the flames and the initial explosion knocked us off our feet.
"We could see the heat from the flames and it was light like day time...
"There were two short explosions larger than anything we've seen since.
"The secondary explosions immediately followed."
He added: "The heat is pretty intense."